Hold your horses. Your first draft is far from being ready for an editor. Prepping it takes more than running it through spell check. Now it’s time to revise.
Revision is the act of rewriting. You want to tighten those rough spots, make sure all your plot points are in place, and your characters are fully fleshed. Is your ending satisfying or is it too easy? Did the story gods drop down and wave their magic wand to make sure everything worked out the way you wanted? If so, your characters need to work harder, and so do you.
You may need to make several passes through your book to catch as many issues as you can. No one writes perfectly in their rough draft… no one. Revisions may make minor changes like character names or places that sound too much alike to full blown reworkings of the plot. If you’re not sure what needs to be rewritten, have someone you trust read it. By trust, I mean someone you trust to be honest, not someone who will just tell you it’s wonderful. Is it important to explain why your main character ran away from home? If it leaves a hole in the story if you leave it out, find a way to include it so it fits in naturally.
Do you have big paragraphs stuffed full of exposition? Find a way to make it interesting and break it up a bit. Can we get that important information without dumping it in? Maybe you can work in some of it in a conversation, or in a letter addressed to the character in question. However you do it, it needs to flow.
After revision 3, 6, or 10, you may be ready to do a final clean up. This is where you make sure you dotted your i’s and crossed your t’s. Are all your punctuation marks in the right place? Spelling has been checked? After you’ve done all of this, then it’s time to contact an editor. You’ll get more for your editing dollar if all the mess has been cleared up first. The remaining issues can then be addressed without digging for them under the slag that should have been taken care of first. Don’t be afraid of revising.